The present invention relates to a measuring arrangement for contactless measurement of electric currents by a measuring coil arrangement and a compensating coil arrangement, wherein a common signal of the measuring coil arrangement and the compensating coil arrangement is detectable by a first detection device.
The invention furthermore relates to a method for contactless electric current measurement in an electric conductor, wherein a signal is generated in a measuring coil arrangement by induction from the electric conductor and the measuring coil arrangement has assigned to it a compensating coil arrangement.
It is known to carry out contactless electric current measurements using so-called current clamps, in which an openable, ring-shaped core is placed around an electric conductor and a magnetic field of the electric conductor is received and inductively measured by the core. Here, the ring-shaped core must be opened and closed for each measurement, which may be complicated if many electric conductors are intended to be measured and/or if the electric conductors are difficult to access.
It is advantageous for the core or the coil to describe a closed ring around the electric conductor for a measurement which is free from interference by externally generated magnetic fields, i.e. magnetic fields generated outside of the electric conductor.
Coil arrangements which deviate herefrom and which have compensating coils for compensating interference fields are also known. In these arrangements, a common signal induced in the measuring coil and in an assigned compensating coil is detected and evaluated.